SwiftKey Keyboard

Keyboards are a dime a dozen these days. But the one that keeps us coming back is SwiftKey. That's as much for its ease of use as its legendary prediction algorithms — its "Fluency Engine," which helps your phone seem to know what to type before you do.

Prediction was always SwiftKey's bread and butter — for years it was leaps and bounds better than Google's stock keyboard, or SwiftKey's arch rival, Swype. Today, it's picked up features made popular by its competitors — the "Flow" swiping method for typing, for one — added cloud sync so you never lose your customized predictions, and it's easier than ever to tie it in to your Google, Facebook or Twitter accounts, so SwiftKey can learn even more about what and how you type.

In 2014, SwiftKey shook things up again by becoming a free app, adding emoji, and offering up various themes, available via an in-app purchase.